30 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



Subfamily Cephalobinae. 



Genera: Cephalobus Bastian, 1865 (syn. Plectonchiis Fuchs, 1930; sg. 

 Neocephalobus Steiner, 1929) ; Aloinema A. Schneider, 1859; Rhab- 

 ditophanes Fuchs, 1930; Panagrolainius Fuchs, 1930; Poikilolaimus 

 Fuchs, 1930; Diastolaimus Rahm, 1930; Acroheloides Cobb, 1924; 

 Acroheles Linstow, 1877; Plectonchus Fuchs, 1930; Chamhersiella 

 Cobb, 1920; Panagrolainius Fuchs, 1930; Teratocephalus de Man, 

 1876 (syn. FMitrephoros Linstow, 1877); ? Choronema Cobb, 1920. 



Subfamily Cephalobiinae. 



Genus: Cephalohhim Cobb, 1920. The objections of Peters to the use of 

 the old name, well established and universally used since Bastian, are 

 at least questionable. Even if they should prove to be valid, an ex- 

 ception to the rules of priority should be made for this case. 



Subfamily Bunoneminae. 



Genera: Bunonema Jagerskiold, 1905; Craspedonema Richters, 1908; Rho- 

 dolaimiis Fuchs, 1930. 



Subfamily Rhabdiasinae. 



Genera: Rhahdias Stiles and Hassall, 1905 (syn. Rhabdonema Leuckart, 

 1879, preocc.) ; Strongyloidcs Grassi, 1879 (syn. Pseudorhabditis Per- 

 roncito, 1880; syn. Stercoralis Tanaka, 1910). 



KEY TO SUBFAMILIES OF ANGUILLULIDAE 



1. (9) Free-living or saprozoic forms; monogenetic. The 



cardiac bulb developed, with masticatory plates. 



2. (5) No special differentiation of the cuticle (aside from 



lateral wings and the male bursa in some forms). 



3. (4) The large part of the wall of the mouth capsule 



consisting of only one ring of chitinous plates. 



Anguillulinae 



4. (3) The wall of the mouth capsule consisting of several 



rings of plates with a thinner cuticle between 



them Cephalobinae 



5. (2) Cuticle with peculiar differentiations, such as asym- 



metrical knobs, wings, or similar things Bunoneminae 



6. (9) Parasites of insects. 



7. (8) Parasites of the body cavity of insects. Body en- 



larged with a spacious body cavity Steinerneminae 



8. (7) Parasites of the intestine. Body filiform without a 



large body cavity Cephalobiniinae 



9. (6) Digenetic: the free-living generation very like, 



sometimes indistinguishable from, the Anguillu- 

 linae; the parasite generation consisting of 

 syngonic females only, with a uniform muscular 



esophagus Rhabdiasinae 



In this family are united all the forms show^ing a simple esopha- 

 gus as in most other nematodes, i.e., without a division into anterior 

 muscular and posterior glandular portion as in the following family. 

 The free-living saprozoic forms have a very characteristic cardiac 

 bulb with masticatory plates inside, which is always the chief, or at 

 least an important, part of the muscular esophageal pump. The pre- 



